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Annals of the New York Academy of... Oct 2013Phosphorus intake in excess of the nutrient needs of healthy adults is thought to disrupt hormonal regulation of phosphorus (P), calcium (Ca), and vitamin D,... (Review)
Review
Phosphorus intake in excess of the nutrient needs of healthy adults is thought to disrupt hormonal regulation of phosphorus (P), calcium (Ca), and vitamin D, contributing to impaired peak bone mass, bone resorption, and greater risk of fracture. Elevation of extracellular phosphorus due to excessive intake is thought to be the main stimulus disrupting phosphorus homeostasis in healthy individuals, as it is in renal disease even when intake is modest. If high serum phosphorus is the critical link to the effect of high phosphorus intake on bone health, the issue could be addressed through epidemiologic or dietary studies. However, several confounding factors, including problems estimating accurate phosphorus intake, the influence of a low dietary Ca:P ratio, the acidic nature of phosphorus, the rapid rate of absorption and greater phosphorus bioavailability from processed food such as cola drinks, and circadian fluctuation in serum phosphorus, make this question difficult to address using conventional study designs. These confounding factors are considered in this review, exploring whether phosphorus intake exceeding nutrient needs in healthy individuals disrupts phosphorus regulation and negatively affects bone accretion or loss. Specific attention is given to phosphorus intake from processed foods rich in phosphorus additives, which significantly contribute to phosphorus intake.
Topics: Bone Density; Bone Diseases; Bone Resorption; Bone and Bones; Calcium; Fibroblast Growth Factor-23; Food Additives; Humans; Phosphates; Phosphorus, Dietary; Renal Insufficiency, Chronic
PubMed: 24472074
DOI: 10.1111/nyas.12300 -
Clinical Journal of the American... Feb 2011Patients with advanced chronic kidney disease (CKD) are in positive phosphorus balance, but phosphorus levels are maintained in the normal range through phosphaturia... (Comparative Study)
Comparative Study Randomized Controlled Trial
BACKGROUND AND OBJECTIVES
Patients with advanced chronic kidney disease (CKD) are in positive phosphorus balance, but phosphorus levels are maintained in the normal range through phosphaturia induced by increases in fibroblast growth factor-23 (FGF23) and parathyroid hormone (PTH). This provides the rationale for recommendations to restrict dietary phosphate intake to 800 mg/d. However, the protein source of the phosphate may also be important.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS
We conducted a crossover trial in nine patients with a mean estimated GFR of 32 ml/min to directly compare vegetarian and meat diets with equivalent nutrients prepared by clinical research staff. During the last 24 hours of each 7-day diet period, subjects were hospitalized in a research center and urine and blood were frequently monitored.
RESULTS
The results indicated that 1 week of a vegetarian diet led to lower serum phosphorus levels and decreased FGF23 levels. The inpatient stay demonstrated similar diurnal variation for blood phosphorus, calcium, PTH, and urine fractional excretion of phosphorus but significant differences between the vegetarian and meat diets. Finally, the 24-hour fractional excretion of phosphorus was highly correlated to a 2-hour fasting urine collection for the vegetarian diet but not the meat diet.
CONCLUSIONS
In summary, this study demonstrates that the source of protein has a significant effect on phosphorus homeostasis in patients with CKD. Therefore, dietary counseling of patients with CKD must include information on not only the amount of phosphate but also the source of protein from which the phosphate derives.
Topics: Aged; Biomarkers; Calcium; Chronic Disease; Cross-Over Studies; Diet, Vegetarian; Dietary Proteins; Female; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Glomerular Filtration Rate; Homeostasis; Humans; Indiana; Kidney Diseases; Linear Models; Male; Meat; Middle Aged; Parathyroid Hormone; Phosphorus, Dietary; Plant Proteins; Time Factors
PubMed: 21183586
DOI: 10.2215/CJN.05040610 -
Ambio Jan 2018Dietary phosphorus frequently exceeds age-specific requirements and pig manure often contains high phosphorus load which causes environmental burden at regional scales....
Dietary phosphorus frequently exceeds age-specific requirements and pig manure often contains high phosphorus load which causes environmental burden at regional scales. Therefore, feeding strategies towards improved phosphorus efficiency and reduced environmental phosphorus load have to be developed. A 5-week feeding trial was conducted: piglets received medium, lower (-25%), or higher (+25%) amounts of phosphorus and calcium. Dietary responses were reflected by performance parameters, bone characteristics, and molecular data retrieved from serum, intestinal mucosa, and kidney cortex (p < 0.05). Transcripts associated with vitamin D hydroxylation (Cyp24A1, Cyp27A1, Cyp27B1) were regulated by diet at local tissue sites. Low-fed animals showed attempts to maintain mineral homoeostasis via intrinsic mechanisms, whereas the high-fed animals adapted at the expense of growth and development. Results suggest that a diet containing low phosphorus and calcium levels might be useful to improve resource efficiency and to reduce phosphorus losses along the agricultural value chain.
Topics: Animal Welfare; Animals; Calcium, Dietary; Diet; Phosphorus; Phosphorus, Dietary; Swine
PubMed: 29159450
DOI: 10.1007/s13280-017-0969-8 -
Physiology (Bethesda, Md.) Feb 2009Phosphorus plays a critical role in diverse biological processes, and, therefore, the regulation of phosphorus balance and homeostasis are critical to the well being of... (Review)
Review
Phosphorus plays a critical role in diverse biological processes, and, therefore, the regulation of phosphorus balance and homeostasis are critical to the well being of the organism. Changes in environmental, dietary, and serum concentrations of inorganic phosphorus are detected by sensors that elicit changes in cellular function and alter the efficiency by which phosphorus is conserved. Short-term, post-cibal responses that occur independently of hormones previously thought to be important in phosphorus homeostasis may play a larger role than previously appreciated in the regulation of phosphorus homeostasis. Several hormones and regulatory factors such as the vitamin D endocrine system, parathyroid hormone, and the phosphatonins (FGF-23, sFRP-4, MEPE) among others, may play a role only in the long-term regulation of phosphorus homeostasis. In this review, we discuss how organisms sense changes in phosphate concentrations and how changes in hormonal factors result in the conservation or excretion of phosphorus.
Topics: Animals; Fibroblast Growth Factor-23; Homeostasis; Humans; Intestinal Mucosa; Kidney; Parathyroid Hormone; Phosphorus; Phosphorus, Dietary; Time Factors; Vitamin D
PubMed: 19196648
DOI: 10.1152/physiol.00034.2008 -
Animal : An International Journal of... Aug 2018The ability of birds to modify dietary phosphorus utilisation when fed with low-phosphorus and calcium (Ca) diets was studied using different sequences of dietary...
The ability of birds to modify dietary phosphorus utilisation when fed with low-phosphorus and calcium (Ca) diets was studied using different sequences of dietary phosphorus and Ca restriction (depletion) and recovery (repletion) during the grower and the finisher phases. A total of 3600 Ross 708 broilers were randomly divided into 10 replicate pens per treatment (60 per pen, six pens per block). Chicks were fed a common starter diet from days 0 to 10, then a grower control diet (C: 0.90% Ca, 0.39% non-phytate phosphorus, nPP), mid-level diet (M: 0.71% Ca, 0.35% nPP) or low Ca and nPP diet (L: 0.60% Ca, 0.30% nPP) from days 11 to 21, followed by a finisher diet C, M or L containing, respectively, 0.85%, 0.57% or 0.48% Ca and 0.35%, 0.29% or 0.24% nPP from days 22 to 37. Six treatment sequences were tested: CC, MM, LL, ML, LC and LM. Bone mineral content by dual-energy X-ray, tibia ash, toe ash weight and tibia breaking strength were measured on days 21 and 37. No significant effect was observed on growth performance throughout the experiment. Diet L reduced bone mineral content, breaking strength, tibia and toe ash by 9%, 13%, 11% and 10%, respectively, on day 21 (compared with diet C, for linear effect, P<0.05). On day 37, bone mineral content, breaking strength, tibia and toe ash remained lower compared with control values (CC v. MM v. LL, P<0.05 for linear and quadratic effects). Mineral depletion duration (ML v. LL) did not affect bone mineral status. Replenishing with the C diet during the finisher phase (LC) restored bone mineral content, tibia ash and toe ash weight better than the M diet did, but not to control levels (CC v. LC v. LM, for linear effect, P<0.05). These results confirm that dietary Ca and nPP may be reduced in the grower phase without affecting final growth performance or breaking strength as long as the finisher diet contains sufficient Ca and nPP. The practical applications of this strategy require further study in order to optimise the depletion and repletion steps.
Topics: 6-Phytase; Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Calcium, Dietary; Chickens; Diet; Dietary Supplements; Phosphorus; Phosphorus, Dietary
PubMed: 29198231
DOI: 10.1017/S1751731117003093 -
Poultry Science Nov 2020Exogenous phytase supplementation increases P and Ca availability to allow for the dietary reductions without negative consequences on productivity or skeletal health....
Effects of dietary calcium and available phosphorus levels and phytase supplementation on performance, bone mineral density, and serum biochemical bone markers in aged white egg-laying hens.
Exogenous phytase supplementation increases P and Ca availability to allow for the dietary reductions without negative consequences on productivity or skeletal health. Effects of a Buttiauxella sp. phytase (BSP) supplemented in available P (avP)-reduced and Ca-reduced diets on performance, BW, eggshell quality, serum biochemical bone markers, and bone densitometry were evaluated in egg-laying hens from 68 to 78 wk of age. One hundred hens were fed 1 of 5 diets (n = 20/treatment), including a positive control (PC) with 0.35% avP and 3.5% Ca, and the PC moderately reduced in avP and Ca levels by 0.187 and 0.159% of the diet (by 53 and 4.5%), respectively, (NC1) or severely reduced by 0.231 and 0.275% of the diet (by 66 and 7.9%), respectively, (NC2). Other diets were the NC1 or NC2 supplemented with BSP at 600 FTU/kg (NC1 + BSP or NC2 + BSP, respectively). Egg production and feed conversion ratio were maintained by NC1 but were 11.9% lower and 12.3% higher, respectively, with the NC2 than the PC, which was alleviated by supplemental BSP. Diet effects on FI and eggshell quality followed a similar pattern. Body weight was 2.9% lower for NC1, and 6.1% for NC2 than the PC; BSP alleviated the decreased BW. Serum pyridinoline (bone resorption marker) was 20 to 27% higher in NC2 hens than in the other groups, with no effects on other bone markers. Total and trabecular space bone mineral density in the proximal metaphysis were 8.4 and 15.2% lower for NC1, respectively, and 12.1 and 26.7% lower for NC2, respectively, than PC. Supplemental BSP completely alleviated the decreased bone densitometry measures in NC1, but only partially in NC2. The NC1 hens maintained performance but had decreased BW and bone quality; phytase supplementation restored productivity, BW, and bone quality. The Ca and avP deficiencies in the NC2 hens relative to other groups were partially alleviated by the 600 FTU/kg BSP.
Topics: 6-Phytase; Animal Feed; Animals; Bone Density; Calcium, Dietary; Chickens; Diet; Dietary Supplements; Egg Shell; Female; Phosphorus, Dietary
PubMed: 33142497
DOI: 10.1016/j.psj.2020.06.082 -
BMC Genomics Mar 2018In monogastric animals, phosphorus (P) homeostasis is maintained by regulating intestinal absorption, bone mobilization, and renal excretion. Since P is a non-renewable...
BACKGROUND
In monogastric animals, phosphorus (P) homeostasis is maintained by regulating intestinal absorption, bone mobilization, and renal excretion. Since P is a non-renewable resource, a shortage is imminent due to widespread over-usage in the farming and animal husbandry industries. As a consequence, P efficiency should be improved in pig production. We sought to characterize the transcriptional response in re-/absorbing and excreting tissues in pigs to diets varying in calcium: phosphorus ratios. Weaned piglets were assigned to one of three groups fed diets varying in digestible P content for a period of five weeks. Gene expression profiles were analyzed in jejunum, colon, and kidney.
RESULTS
Transcriptome analysis revealed that reduced dietary P intake affects gene expression in jejunum and kidney, but not in colon. The regulation of mineral homeostasis was reflected via altered mRNA abundances of CYP24A1, CYP27A1, TRPM6, SPP1, and VDR in jejunum and kidney. Moreover, lowered abundances of transcripts associated with the classical complement system pathway were observed in the jejunum. In kidney, shifted transcripts were involved in phospholipase C, calcium signaling, and NFAT signaling, which may have immunomodulatory implications.
CONCLUSIONS
Our results revealed local transcriptional consequences of variable P intake in intestinal and renal tissues. The adaptive responses are the result of organismal efforts to maintain systemic mineral homeostasis while modulating immune features at local tissue sites. Therefore, the deviation from the currently recommended dietary P supply must be carefully considered, as the endogenous mechanisms that respond to low P diets may impact important adaptive immune responses.
Topics: Animal Nutritional Physiological Phenomena; Animals; Animals, Newborn; Colon; Gene Expression Profiling; Gene Expression Regulation; Homeostasis; Intestinal Mucosa; Jejunum; Kidney; Minerals; Phosphorus, Dietary; Swine; Weaning
PubMed: 29554878
DOI: 10.1186/s12864-018-4584-2 -
Advances in Nutrition (Bethesda, Md.) Jan 2014It is important to consider whether habitual high phosphorus intake adversely affects bone health, because phosphorus intake has been increasing, whereas calcium intake... (Review)
Review
It is important to consider whether habitual high phosphorus intake adversely affects bone health, because phosphorus intake has been increasing, whereas calcium intake has been decreasing in dietary patterns. A higher total habitual dietary phosphorus intake has been associated with higher serum parathyroid hormone (PTH) and lower serum calcium concentrations in healthy individuals. Higher serum PTH concentrations have been shown in those who consume foods with phosphorus additives. These findings suggest that long-term dietary phosphorus loads and long-term hyperphosphatemia may have important negative effects on bone health. In contrast, PTH concentrations did not increase as a result of high dietary phosphorus intake when phosphorus was provided with adequate amounts of calcium. Intake of foods with a ratio of calcium to phosphorus close to that found in dairy products led to positive effects on bone health. Several randomized controlled trials have shown positive relations between dairy intake and bone mineral density. In our loading test with a low-calcium, high-phosphorus lunch provided to healthy young men, serum PTH concentrations showed peaks at 1 and 6 h, and serum fibroblast growth factor 23 (FGF23) concentrations increased significantly at 8 h after the meal. In contrast, the high-calcium, high-phosphorus meal suppressed the second PTH and FGF23 elevations until 8 h after the meal. This implies that adequate dietary calcium intake is needed to overcome the interfering effects of high phosphorus intake on PTH and FGF23 secretion. FGF23 acts on the parathyroid gland to decrease PTH mRNA and PTH secretion in rats with normal kidney function. However, increased serum FGF23 is an early alteration of mineral metabolism in chronic kidney disease, causing secondary hyperthyroidism, and implying resistance of the parathyroid gland to the action of FGF23 in chronic kidney disease. These findings suggest that long-term high-phosphorus diets may impair bone health mediated by FGF23 resistance both in chronic kidney disease patients and in the healthy population.
Topics: Animals; Bone Resorption; Bone and Bones; Congresses as Topic; Fast Foods; Feeding Behavior; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Food Additives; Humans; Parathyroid Glands; Parathyroid Hormone; Phosphorus, Dietary
PubMed: 24425727
DOI: 10.3945/an.113.004002 -
PloS One 2018Intestinal phosphorus absorption is an important component of whole-body phosphorus metabolism, and limiting dietary phosphorus absorption is particularly of interest as...
Intestinal phosphorus absorption is an important component of whole-body phosphorus metabolism, and limiting dietary phosphorus absorption is particularly of interest as a therapeutic target in patients with chronic kidney disease to manage mineral bone disorders. Yet, mechanisms and regulation of intestinal phosphorus absorption have not been adequately studied and discrepancies in findings exist based on the absorption assessment technique used. In vitro techniques show rather consistent effects of dietary phosphorus intake level and age on intestinal sodium-dependent phosphate transport. But, the few studies that have used in vivo techniques conflict with these in vitro studies. Therefore, we aimed to investigate the effects of dietary phosphorus intake level on phosphorus absorption using the in situ ligated loop technique in three different aged rats. Male Sprague-Dawley rats (n = 72), were studied at 10-, 20-, and 30-weeks-of-age on a low (0.1%), normal (0.6%), or high (1.2%) phosphorus diet in a 3x3 factorial design (n = 8/group). Rats were fed their assigned diet for 2-weeks prior to absorption testing by jejunal ligated loop as a non-survival procedure, utilizing 33P radioisotope. Metabolic cages were used for determination of calcium and phosphorus balance over the final four days prior to sacrifice, and blood was collected at the time of sacrifice for biochemistries. Our results show that phosphorus absorption was higher in 10-week-old rats compared with 20- and 30-week-olds and this corresponded to higher gene expression of the major phosphate transporter, NaPi-2b, as well as higher whole-body phosphorus balance and net phosphorus absorption. Dietary phosphorus intake level did not affect jejunal phosphorus absorption or NaPi-2b gene expression. Our results contrast with studies utilizing in vitro techniques, but corroborate results of other rodent studies utilizing in situ or in vivo methods. Thus, there is need for additional studies that employ more physiological methods of phosphorus absorption assessment.
Topics: Animals; Calcium; Intestinal Absorption; Intestines; Male; Phosphorus, Dietary; Rats; Rats, Sprague-Dawley; Sodium-Phosphate Cotransporter Proteins, Type IIb; Up-Regulation
PubMed: 30452474
DOI: 10.1371/journal.pone.0207601 -
Archives of Razi Institute Feb 2023Phytic acid is a stored form of phosphorus in cereals, 65 to 70% of phosphorus in plant sources is phytate, and broilers are only able to use part of the phosphorus in...
Phytic acid is a stored form of phosphorus in cereals, 65 to 70% of phosphorus in plant sources is phytate, and broilers are only able to use part of the phosphorus in plant sources. To meet the needs of chickens, it is necessary to use other artificial resources, which not only impose part of the cost of the breeding period because of its presence in the manure but is one of the factors polluting the environment. This study aimed to use different levels of phytase enzyme to reduce dietary phosphorus levels. 600 Ross 308 broilers were used in this experiment with five treatments and six replications, and in each replication, 20 chickens were used in a completely randomized design (CRD). Experimental treatments include 1) basal diet (control) 2) basal diet with 15% less phosphorus 3) basal diet with 15% less phosphorus + 1250 (FTU) phytase enzyme 4) basal diet with 15% less phosphorus + 2500 (FTU) phytase enzyme 5) basal diet with 15% less phosphorus + 5000 (FTU) phytase enzyme. The evaluated traits included weekly feed intake, weekly weight gain, feed conversion ratio, carcass characteristics, ash, calcium, and bone phosphorus. The use of phytase enzyme in different diets had no significant effect on food intake, weight gain, and feed conversion ratio (>0.05). However, the use of phytase in different diets significantly affected the percentage of Gizzard, Heart, Liver, Proventriculus, and Spleen (<0.05). The most changes were the increase in the ratio of feed intake and weight gain in the fourth week compared to the third week so that the changes in the ratio of feed intake ranged from 1.85 to 1.91, and this ratio for weight gain also ranged from 3.12 to 3.86 was recorded, and the lowest feed conversion ratio was obtained at the same age. The percentage of raw ash in broiler chickens was significantly increased by adding dietary phytase. The lowest amount of ash, calcium, and phosphorus belonged to the second group (diets with low phosphorus and no enzyme). The difference between the other groups and the control was not significant. Feed intake, weight gain, and feed conversion ratio with the addition of phytase enzyme were not affected by phosphorus reduction and had no significant effect on carcass characteristics. Environmental pollution can be prevented by reducing the level of dietary phosphorus and reducing excreted phosphorus.
Topics: Animals; 6-Phytase; Calcium; Chickens; Phosphorus; Phosphorus, Dietary; Phytic Acid
PubMed: 37312704
DOI: 10.22092/ARI.2022.359524.2443